The present invention relates to a method and apparatus for dispensing materials from large, flexible bags.
Materials such as granular salt are commonly packaged in bulk bags, which contain a large quantity of material and are quite heavy, and from which relatively small quantities of the material can be dispensed into smaller containers over a period of time. One type of known bulk bag has openings at its upper and lower ends which may be held closed by drawstrings and has a pair of straps attached near its upper end to enable the bulk bag to be suspended from an overhead support. This type of bag may be used in combination with an inner liner which seals the material inside the bag from dirt, moisture, and air. Such inner liners are generally used where a food grade product, such as salt, is contained within the bag. The inner liners are commonly made of thin, flexible plastic material .
A known method for dispensing material from bags of this type comprises suspending the bulk bag from an overhead support by the straps, opening the lower end of the bag at the lower drawstring, and slitting the inner liner to enable the material to flow downwardly out of the lower end of the bag. The bag may then be reclosed after a desired quantity has been dispensed by pulling the drawstring closed.
One disadvantage of this method is that it may be unsafe to suspend the bulk bag, which contains a large amount of product, from an overhead support by the straps. Opening the drawstring at the bottom of the bag and slitting the inner liner may require a worker to stand beneath the bag in such a position that the worker is vulnerable to injury should one of the straps or the overhead support fail.
Another disadvantage of this method is that repeatedly opening and closing the bag with the drawstring is inefficient and inconvenient, particularly where a single bag must be opened and closed a large number of times to fill a large number of relatively small containers.